d-Au and p-p collisions at RHIC and the multichain Monte Carlo Dpmjet-III

In this paper we compare systematically the two-component Dual Parton Model (DPM) event generator Dpmjet-III to d-Au and p-p data from RHIC. In this process we are able to improve the model. The need for fusion of chains and a recalibration of the model to obtain collision scaling in h-A and d-A collisions was found already in previous comparisons. Here, comparing to transverse momentum distributions of identified charged hadrons we find also the need to modify the transverse momentum distributions in the decay of hadronic strings, the basic building blocks of the model on soft hadronic collisions.Comment: 8 pages, 13 figures, Based on a contribution to a workshop "QCD at Cosmic Energies, Erice, Italie, Aug.29 to Sept.5 200

Antibaryon to Baryon Production Ratios in Pb-Pb and p-p collision at LHC energies of the DPMJET-III Monte Carlo

A sizable component of stopped baryons is predicted for pp and P bP b collisions at LHC. Based on an analysis of RHIC data within framework of our multichain Monte Carlo DPMJET-III the LHC predictions are presented.Comment: Presented at "Heavy Ion Collisions at the LHC: last call for predictions", Geneva Switzerland, May 14th-June 8t

RHIC data and the multichain Monte Carlo DPMJET-II

Using data from RHIC we are able to systematically improve the two-component Dual Parton Model (DPM) event generator DPMJET-III. Introducing percolation parametrized as fusion of chains the model describes multiplicities and pseudorapidity distributions in nucleus-nucleus collisions at all centralities. Guided by the d-Au data from RHIC we recalibrate the model to obtain collision scaling in h-A and d-A collisions.Comment: 8 pages, Based on a poster submitted to the 17th International Conference on Ultra Relativistic Nucleus Nucleus Collisions, Jan. 11-17, Oakland,California US

Antiparticle to Particle Production Ratios in Hadron-Hadron and d-Au Collisions in the DPMJET-III Monte Carlo

To understand baryon stopping we analyse new RHIC and Fermilab data within the framework of the multichain Monte Carlo DPMJET-III. The present consideration is restricted to to hadron-hadron and d-Au collisions.Comment: 10 pages, 19 figures. The paper is expanded in a mayor way to include more dat

Inclusive distributions at the LHC as predicted from the DPMJET-III model with chain fusion

DPMJET-III with chain fusion is used to calculate inclusive distributions of Pb-Pb collisions at LHC energies. We present rapidity distributions as well as scaled multiplicities at mid-rapidity as function of the collision energy and the number of participants.Comment: Presented at "Heavy Ion Collisions at the LHC: last call for predictions", Geneva Switzerland, May 14th-June 8t

Initial State: Theory Status

I present a brief discussion of the different approaches to the study initial state effects in heavy ion collisions in view of the recent results from Pb+Pb and p+p collisions at the LHC.Comment: 8 pages, 6 figures. Contribution to the proceedings of the XXII International Conference on Ultrarelativistic Nucleus-Nucleus Collisions, QM2011. Annecy, France, 22-28 May 201

Particle production azimuthal asymmetries in a clustering of color sources model

The collective interactions of many partons in the first stage of the collisions is the usual accepted explanation of the sizable elliptical flow. The clustering of color sources provides a framework of partonic interactions. In this scheme, we show a reasonable agreement with RHIC data for pT<1.5 GeV/c in both the dependence of v2 transverse momentum and in the shape of the nuclear modified factor on the azimuthal angle for different centralities. We show the predictions at LHC energies for Pb-Pb. In the case of proton-proton collisions a sizable v2 is obtained at this energy.Comment: To appear in Journal of Physics

Hard diffraction in hadron--hadron interactions and in photoproduction

Hard single diffractive processes are studied within the framework of the triple--Pomeron approximation. Using a Pomeron structure function motivated by Regge--theory we obtain parton distribution functions which do not obey momentum sum rule. Based on Regge-- factorization cross sections for hard diffraction are calculated. Furthermore, the model is applied to hard diffractive particle production in photoproduction and in $p\bar{p}$ interactions.Comment: 13 pages, Latex, 13 uuencoded figure

Hadronic photon-photon interactions at high energies

Photon-photon collisions are investigated in the framework of the two-component Dual Parton Model. The model is shown to agree well to hadron production data from hadron-hadron and photon-hadron collisions. The multiparticle production in hadron-hadron, photon-hadron and photon-photon collisions as predicted by the model is compared. Strong differences are only found as function of the transverse momentum variable. The hadron production in photon-photon collisions at present and future electron-positron colliders is studied using photon spectra according to the equivalent photon approximation, according to beamstrahlung and according to backscattered laser radiation.Comment: 18 pages + 26 figures, latex with poscript figures uuencode

Photoproduction off Nuclei and Point-like Photon Interactions Part I: Cross Sections and Nuclear Shadowing

High energy photoproduction off nuclear targets is studied within the Glauber-Gribov approximation. The photon is assumed to interact as a $q\bar{q}$-system according to the Generalized Vector Dominance Model and as a ``bare photon'' in direct scattering processes with target nucleons. We calculate total cross sections for interactions of photons with nuclei taking into account coherence length effects and point-like interactions of the photon. Results are compared to data on photon-nucleus cross sections, nuclear shadowing, and quasi- elastic $\rho$-production. Extrapolations of cross sections and of the shadowing behaviour to high energies are given.Comment: 15 pages, 12 figure